How to Fix a Chalky Gel Coat

Gel coat is a resin-based product, mixed with color, that is commonly used on boats and other fiberglass surfaces. Gel coat produces a nice sheen and also provides a protective barrier against natural elements such as water. One problem with gel coats, usually lower quality gel coats, is that the surface eventually develops a chalky appearance. The chalky appearance is caused by oxidation. Oxidation detracts from the appearance of a boat, and an oxidized surface compromises the protective barrier. Removing the traces of oxidation and restoring the finish requires a little bit of effort and elbow grease.

Things You'll Need

  • Mild detergent
  • Bucket
  • Household bleach
  • Sponge
  • Sandpaper (800 to 1600 grit)
  • Carnauba wax
  • Soft cloth
  • Buffing pad
  • Electric buffer
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Instructions

    • 1

      Clean the surface thoroughly with a mild detergent and lukewarm water. Mix 1 cup of detergent with 1 gallon of water in a bucket. Add 1 cup of bleach to deal with a mildew problem. Clean the surface with a sponge. Rinse with clean water and allow the surface to thoroughly dry.

    • 2

      Wet-sand the chalky surface areas with 800-grit sandpaper. Repeat the process with 1200- and 1600-grit sandpaper.

    • 3

      Apply 3M wax or a similar carnauba wax to the surface. Carnauba wax, also referred to as Brazil wax or palm wax, is regarded as the queen of waxes. 3M wax is available at home supply stores as well as auto parts stores. Apply the wax with a soft, clean cloth. Allow the wax to remain on the surface for a few minutes until it hazes over.

    • 4

      Buff the surface with a buffing pad. Attach the buffing pad to an electric buffer. Buff the wax using circular motions. Continue buffing until the surface has a nice sheen.